UPDATE 1-US appeals court affirms ruling on Risperdal patent

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WASHINGTON May 11 (Reuters) - A U.S. appeals court upheld
a lower court ruling on Friday that blocked U.S. sales of two
copycat versions of the Johnson & Johnson (JNJ.N) antipsychotic
drug Risperdal until a J&J patent expires at the end of 2007.

The U.S. Court of Appeals for the Federal Circuit affirmed
rulings by a lower court judge in New Jersey that upheld the
validity of a key J&J patent on the drug and delayed the
effective date of a tentative approval given to Mylan
Pharmaceuticals Inc. , a unit of Mylan Laboratories Inc.
MYL.N to market its generic Risperdal.